Charlie is frying an egg in a pan located over a gas burner. He develops a model to determine the energy produced by the flame in the gas burner by calculating the energy absorbed by the egg. Which assumption will Charlie need to make in order for his model to be considered a
closed system?
A. Heat flows from the egg to the surroundings.
O
B. Heat flows from the pan to the surroundings.
O
C. No heat is lost from the flame or the egg to the surroundings.
OD. The egg receives heat from the flame and the surroundings.

A closed system is one in which there is no exchange of materials or energy with the surroundings hence the correct assumption is that "No heat is lost from the flame or the egg to the surroundings."

Another name for a closed system is an isolated system. In such system, there is exchange of material or energy between the system and the surroundings.

In this case, the system comprises of the pan and the eggs. If the system is to be a closed system then " No heat is lost from the flame or the egg to the surroundings."

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answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.